Rockwell Automation DeviceNet Media Design Installation Guide
DeviceNet Media
Design and Installation Guide
Important User Information
Solid state equipment has operational characteristics differing from those of
electromechanical equipment. Safety Guidelines for the Application, Installation and
Maintenance of Solid State Controls (Publication SGI-1.1 available from your local
Rockwell Automation sales office or online at http://www.ab.com/manuals/gi)
describes some important differences between solid state equipment and hard-wired
electromechanical devices. Because of this difference, and also because of the wide
variety of uses for solid state equipment, all persons responsible for applying this
equipment must satisfy themselves that each intended application of this equipment is
acceptable.
In no event will Rockwell Automation, Inc. be responsible or liable for indirect or
consequential damages resulting from the use or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes.
Because of the many variables and requirements associated with any particular
installation, Rockwell Automation, Inc. cannot assume responsibility or liability for
actual use based on the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to use of
information, circuits, equipment, or software described in this manual.
Reproduction of the contents of this manual, in whole or in part, without written
permission of Rockwell Automation, Inc. is prohibited.
Throughout this manual we use notes to make you aware of safety considerations.
WARNING
IMPORTANT
ATTENTION
SHOCK HAZARD
BURN HAZARD
Identifies information about practices or circumstances that can
cause an explosion in a hazardous environment, which may lead
to personal injury or death, property damage, or economic loss.
Identifies information that is critical for successful application
and understanding of the product.
Identifies information about practices or circumstances that can
lead to personal injury or death, property damage, or economic
loss. Attentions help you:
• identify a hazard
• avoid a hazard
• recognize the consequence
Labels may be located on or inside the equipment to alert people
that dangerous voltage may be present.
Labels may be located on or inside the euipment to alert people
that surfaces may be dangerous temperatures.
Preface
What’s in This Manual
Who Should Read This
Manual
Use this manual to design and install a DeviceNet™ cable system. This manual
describes the required components of the cable system and how to design for
and install these required components. This manual also contains a chapter on
general network troubleshooting tips.
TIP
TIP
We assume that you have a fundamental understanding of:
• electronics and electrical codes
• basic wiring techniques
• ac and dc power specifications
• load characteristics of the devices attached to the DeviceNet network
Throughout this manual, we use the terms “unsealed” and
“open” interchangeably.
The catalog numbers listed in this document are
representative of the full range of available DeviceNet
media products. For a complete list of DeviceNet media,
refer to the On-machine Connectivity Catalog,
publication M115-CA001.
1 Publication DNET-UM072C-EN-P - July 2004
2
For Your Reference
Rockwell Automation provides many useful tools for planning and
configuring your DeviceNet network.
for information on refer to go to
selecting a DeviceNet network, as well as
the individual devices you can use on the
network
available DeviceNet-enabled and
conformance-tested products from
Rockwell Automation and other vendors
developer information, standards,
electronic data sheet (EDS) files, etc.
guidelines and safety tips for wiring and
grounding your network
NetLinx Selection Guide, publication
NETS-SG001
DeviceNet Media, Sensors, and Distributed
I/O Catalog, publication 1485-CG001
On-machine Connectivity Catalog, publication
M115-CA001
Integrated Architecture Builder
The Open DeviceNet Vendor Association
product catalog
Rockwell Automation’s networks home page www.ab.com/networks
Industrial Automation Wiring and Grounding
Guidelines, publication 1770-4.1
www.rockwellautomation.com/literature
www.rockwellautomation.com/literature
www.rockwellautomation.com/literature
www.ab.com/logix/iab/download.html
www.odva.org
www.rockwellautomation.com/literature
Publication DNET-UM072C-EN-P - July 2004
3
Using Integrated Architecture Builder (IAB)
Integrated Architecture Builder is a graphical tool designed to help you
configure and quote Logix-based control systems, including validation of
DeviceNet cable power requirements. With IAB, you can build a control
system using a wizard and other common Microsoft Windows tools such as
tree views, drag-and-drop, and cut-copy-paste. IAB also allows you to open
product manuals to help you configure a system. Once you configure the
system, the software performs validity checking, and you can generate a report
to be used in quoting the control system.
Figure Preface.1 shows a sample of the IAB interface you use to build a
system.
Figure Preface.1 Integrated Architecture Builder
You can select control
platforms and components
to build a system. IAB
automatically verifies
system validity.
Publication DNET-UM072C-EN-P - July 2004
4
About the National Electric
Code
About the DeviceNet
Network Hazardous
Environment Rating
Much of the information provided in this manual is representative of the
capability of a DeviceNet network and its associated components. The
National Electric Code (NEC), in the United States, and the Canadian Electric
Code (CECode), in Canada, places limitations on configurations and the
maximum allowable power/current that can be provided.
for details.
IMPORTANT
ATTENTION
During the planning and installation of your DeviceNet
network, research and adhere to all national and local
codes.
The DeviceNet network is not rated for use in hazardous
environments, such as Class1, Div 2 installations.
Refer to Appendix A
Publication DNET-UM072C-EN-P - July 2004
Get Started
Table of Contents
Chapter 1
What’s in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Before You Begin. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Set Up a DeviceNet Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Basic DeviceNet network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Understand the topology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Understand the Media. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Understand the cable options . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Determine the maximum trunk line distance . . . . . . . . . . . . . . . . 1-7
Determine the cumulative drop line length . . . . . . . . . . . . . . . . . 1-9
About direct connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
About connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
Terminate the Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
Guidelines for supplying power . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
Supply Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
Choose a power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
About power ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
Size a power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
Place the power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-18
Connect power supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21
Ground the Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-22
Use the Checklist. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
Identify Cable System Components
Chapter 2
About Thick Cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
About Thin Cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
About Flat Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Connect to the Trunk Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
About the T-Port tap. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
About the DeviceBox tap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
About the PowerTap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
About the DevicePort tap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
About direct connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
About open-style connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
About open-style taps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
About KwikLink Insulation Displacement Connectors (IDCs) 2-15
Use Preterminated Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
About thick cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
About thin cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
About KwikLink drop cables . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
About terminators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
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Table of Contents ii
Make Cable Connections
Chapter 3
Prepare Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Install Open-Style Connectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Install Mini/Micro Sealed Field-Installable Connectors . . . . . . . . . . 3-3
Install DeviceBox and PowerTap Taps. . . . . . . . . . . . . . . . . . . . . . . . 3-4
Install PowerTap Taps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Install DeviceBox Taps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
Install DevicePort Taps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Connect Drop Lines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Install KwikLink Cable and KwikLink Heavy-Duty Connectors . . 3-10
Install a KwikLink open-style connector to a drop cable . . . . . 3-13
Install end caps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
Install Class 1 KwikLink power cable. . . . . . . . . . . . . . . . . . . . . 3-15
Connect a Power Supply to Round Media . . . . . . . . . . . . . . . . . . . . 3-16
Connect Power Supplies to KwikLink Flat Media . . . . . . . . . . . . . . 3-17
Class 1, 8A System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
Class 2, 4A System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
Determine Power Requirements
Correct and Prevent Network
Problems
Chapter 4
Class 1 (CL1) cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Class 2 (CL2) Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Use the Look-up Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
One power supply (end-connected) . . . . . . . . . . . . . . . . . . . . . . 4-11
One power supply (middle-connected). . . . . . . . . . . . . . . . . . . . 4-12
NEC/CECode current boost configuration . . . . . . . . . . . . . . . 4-15
Two power supplies (end-connected) in parallel with no
V+ break . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-16
Two Power supplies (not end-connected) in parallel with no V+
break . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18
Use the Full-calculation Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-20
Use the Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-21
One power supply (end-connected) . . . . . . . . . . . . . . . . . . . . . . 4-22
One power supply (middle-connected). . . . . . . . . . . . . . . . . . . . 4-23
Chapter 5
General Troubleshooting Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
Diagnose Common Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Check System Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Use Terminating Resistors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Ground the Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Diagnose Power Supply Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
When choosing a power supply, keep the following tips
in mind:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Verify Network Voltages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
If voltages are too low . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Publication DNET-UM072C-EN-P - July 2004
Understand Select NEC Topics
Power Output Devices
Index
Table of Contents iii
Appendix A
Specify Article 725 Topics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Round (thick & thin) and Class 2 flat media . . . . . . . . . . . . . . . A-1
Class 1 flat media . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Appendix B
Use DeviceNet Power Supplies to Operate Output Devices . . . . . . B-1
Noise or Transient Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
Publication DNET-UM072C-EN-P - July 2004
Table of Contents iv
Publication DNET-UM072C-EN-P - July 2004
Get Started
Chapter
1
What’s in This Chapter
This chapter introduces the DeviceNet cable system and provides a brief
overview of how to set up a DeviceNet network efficiently. The steps in this
chapter describe the basic tasks involved in setting up a network.
for information on this topic see page
Before You Begin 1-2
Set Up a DeviceNet Network 1-4
Understand the Media 1-5
Terminate the Network 1-13
Supply Power 1-15
Ground the Network 1-22
Use the Checklist 1-24
TIP
The catalog numbers listed in this document are
representative of the full range of available DeviceNet
media products. For a complete list of DeviceNet media,
refer to the On-machine Connectivity Catalog,
publication M115-CA001.
1 Publication DNET-UM072C-EN-P - July 2004
1-2 Get Started
Before You Begin
Before you begin laying out your DeviceNet network, take a few minutes to
consider the following decisions you must make.
1. What control platform should I use?
For help with choosing the correct control platform for the
application, refer to Chapter 2 of the NetLinx Selection Guide,
publication NETS-SG001.
After selecting the control platform, use Chapter 2 of the NetLinx
Selection Guide, publication NETS-SG001, to help you choose the
DeviceNet communication interface for that platform.
TIP
2. What I/O devices will I need?
For help with choosing the correct I/O devices for the application,
refer to Chapter 2 of the NetLinx Selection Guide, publication
NETS-SG001.
Once you have selected all DeviceNet devices for your
network, calculate the total data size required by the
DeviceNet-networked devices. Compare the total data
size required against the total amount available from
the DeviceNet scanner module you have selected.
If you plan to hard-wire certain devices to I/O modules, calculate
the total number of discrete I/O points, such as sensors, photoeyes,
etc., in your application.
TIP
Calculate the total required analog I/O channels.
Calculate the total I/O points being brought into I/O modules
versus direct connections to the network.
Decide which type of discrete I/O you will use in your application:
sealed (such as FLEXArmor or MaXum), or open-style (typically
contained in enclosures).
All DeviceNet-capable devices require a unique
network node number, which counts against the total
node count of 63. If the I/O points are standard
discrete versions, they will be connected to t he
DeviceNet network via a discrete I/O-to-DeviceNet
adapter. In this case, only the I/O adapter would
require a network node number, allowing you to
connect multiple I/O points with one adapter.
Publication DNET-UM072C-EN-P - July 2004
Get Started 1-3
Decide whether to use DeviceLogix/EE-capable I/O to run
internal, programmable logic within the actual devices for fast
execution rates.
Document the data table requirements for each node. This
information will help you develop the control platform user
program.
3. What type of network media is best for my application?
For help in determining which media best fits your application,
refer to the following publications:
for refer to
media characteristics and specifications DeviceNet Media, Sensors, and Distributed
I/O Catalog, publication 1485-CG001
On-machine Connectivity Catalog,
publication M115-CA001
guidelines for wiring and grounding your
network
Industrial Automation Wiring and
Grounding Guidelines, publication 1770-4.1
Determine whether you need a Class 1 or Class 2 cabling system.
Choose sealed or unsealed media for your application’s
environment.
Choose the maximum trunk length allowable within specifications
for the cable type and communication baud rate.
Ensure that your cumulative cable drop length is within
specifications for the network baud rate.
Ensure that all individual drop line lengths are </= 20 ft. (6m).
Ensure that you have one 121Ω terminating resistor at each end of
the trunk line.
4. Which power supply will be adequate for my application?
Refer to this publication for further details on selecting a power
supply.
5. How do I configure my network?
You can use RSNetWorx for DeviceNet software to generate an
offline configuration file which contains all the I/O mapping for
your system. This file will help you develop a control platform user
Publication DNET-UM072C-EN-P - July 2004
1-4 Get Started
program. Refer to the online help accompanying RSNetWorx for
DeviceNet software for assistance in adding and configuring devices.
Once you have added devices, use either RSNetWorx for
DeviceNet software or the device’s hardware mechanism to
commission a node for that device.
Use RSNetWorx for DeviceNet software to create and download a
scanlist to the master scanner.
6. How do I check system performance?
To obtain Rockwell Automation’s off-line performance simulation
tools, visit www.ab.com and click on Support ⇒Knowledgebase
⇒DeviceNet Performance.
Set Up a DeviceNet
Network
1
Understand the
Media
refer to page 1-5
2
Terminate the
Network
refer to page 1-13
3
Supply Power
refer to page 1-15
4
Ground the Network
refer to page 1-22
5
Use the Checklist
refer to page 1-24
The following diagram illustrates the steps that you should follow to plan and
install a DeviceNet network. The remainder of this chapter provides an overview
and examples of each step.
1 Understand the Media Refer to page 1-5
2 Terminate the Network Refer to page 1-13
3 Supply Power Refer to page 1-15
4 Ground the Network Refer to page 1-22
5 Use the Checklist Refer to page 1-24
Publication DNET-UM072C-EN-P - July 2004
Basic DeviceNet network
This figure shows a basic DeviceNet network and calls out its basic components.
Get Started 1-5
1
Understand the
Media
3,4
TR
2
trunk line
drop lines
Power
Supply
TR
5
1
D
terminating resistor
Understand the topology
The DeviceNet cable system uses a trunk/drop line topology.
TR
TR
2
device or node
Checklist
41829
TR
You must terminate the trunk line at both ends
with 121Ω, 1%, 1/4W or larger terminating
resistors.
trunk line
drop line
device or node
TR = terminating resistor
41826
Publication DNET-UM072C-EN-P - July 2004
1-6 Get Started
All Allen-Bradley media, including KwikLink,
meets or exceeds the specifications defined in
the ODVA DeviceNet Specification.
Understand the cable options
You can connect components using three cable options.
Use this cable As
Round (thick) the trunk line on the DeviceNet network
with an outside diameter of 12.2 mm
(0.48 in.). You can also use this cable for
drop lines.
Round (thin) the drop line connecting devices to the main
line with an outside diameter of 6.9 mm
(0.27 in.). This cable has a smaller diameter
and is more flexible than thick cable. You
can also use this cable for the trunk line.
Flat
Class 1 power supplies allow for an 8A
system and the use of Class 1 flat cable.
Class 2 flat cable must not exceed 4A.
KwikLink drop cable a non-shielded, 4-conductor drop cable for
Unshielded drop cable a non-shielded, 4-conductor drop cable
the trunk line on the DeviceNet network,
with dimensions of 19.3 mm x 5.3 mm (0.76
in. x 0.21 in.). This cable has no
predetermined cord lengths, and you are
free to put connections wherever you need
them.
use only in KwikLink systems.
(with an outside diameter specified by the
vendor) for use only in flat cable systems
Publication DNET-UM072C-EN-P - July 2004
Determine the maximum trunk line distance
Get Started 1-7
The maximum cable distance is not
necessarily the trunk length only. It is the
maximum distance between any two devices.
Wire
Color
white CAN_H signal signal
blue CAN_L signal signal
bare drain shield n/a
black V- power power
red V+ power power
Wire
Identity
Usage
Round
Usage
Flat
TIP
Round cable (both thick and thin) contains five wires: One
twisted pair (red and black) for 24V dc power, one twisted
pair (blue and white) for signal, and a drain wire (bare).
Flat cable contains four wires: One pair (red and black) for
24V dc power; one pair (blue and white) for signal.
Drop cable for KwikLink is a 4-wire unshielded gray cable.
It is used only with KwikLink flat cable systems.
The distance between any two points must not exceed the maximum cable
distance allowed for the data rate used.
Data rate Maximum
distance
(flat cable)
125k bit/s 420m (1378 ft) 500m (1640 ft) 100m (328 ft)
250k bit/s 200m (656 ft) 250m (820 ft) 100m (328 ft)
500k bit/s 75m (246 ft) 100m (328 ft) 100m (328 ft)
Maximum
distance
(thick cable)
Maximum
distance
(thin cable)
Publication DNET-UM072C-EN-P - July 2004
1-8 Get Started
p
In most cases, the maximum distance should be the measurement between
terminating resistors. However, if the distance from a trunk line tap to the
farthest device connected to the trunk line is greater than the distance from the
tap to the nearest terminating resistor (TR), then you must include the drop line
length as part of the cable length.
Measure the distance between the terminating resistors.
TR
D
D
Always use the longest distance
between any 2 nodes of the network.
3m (9.843 ft)
TR
D
tap
drop
5m (16.405 ft)
D
taptaptap
drop
D
Measure both drops and across the trunk.
tap
D
tap
D
D
1m (3.281 ft)
tap
D
tap
D
drop
5m (16.405 ft)
3m (9.843 ft)
If the distance from the TR to the last
tap is greater than the distance of
the drop, then measure from the TR.
3m (9.843 ft)
tap
If the distance from
the TR to the last ta
is less than the
distance of the drop,
D
measure from the
device.
TR
D
TR
D
Publication DNET-UM072C-EN-P - July 2004
TIP
41647
To extend the length of your network and
allow longer drop line lengths, you can
purchase a bus extender or wireless DeviceNet
modem from various vendors, such as Western
Reserve Controls, one of Rockwell
Automation’s Encompass partners. Contact
your Rockwell Automation representative for
details.
Determine the cumulative drop line length
Get Started 1-9
The data rate you choose determines the trunk
line length and the cumulative length of the drop
line.
The maximum cable distance from any device
on a branching drop line to the trunk line is 6m
(20 ft).
TR TR
4m (13 ft)
The cumulative drop line length refers to the sum of all drop lines, thick or thin
cable, in the cable system. This sum cannot exceed the maximum cumulative
length allowed for the data rate used.
Data rate Cumulative drop line length
125k bit/s 156m (512 ft)
250k bit/s 78m (256 ft)
500k bit/s 39m (128 ft)
The following example uses four T-Port (single-port) taps and two DevicePort™
(multi-port) taps to attach 13 devices to the trunk line. The cumulative drop line
length is 42m (139 ft) and no single node is more than 6m (20 ft) from the trunk
line. This allows you to use a data rate of 250k
bit/s or 125k bit/s. A data rate of 500k bit/s cannot be used in this example
because the cumulative drop line length (42m) exceeds the total allowed (39m)
for that data rate.
2m (6.6)
2m(6.6 ft)
DevicePort tap
(4 ports)
= trunk line
= drop line
= device or node
TR = terminating resistor
1m
(3.3 ft)
4m (13 ft)
3m (10 ft)
3m (10 ft)
2m (6.6 ft)
3m (10 ft)
3m (10 ft)
2m (6.6 ft)
1m
(3.3 ft)
3m (10 ft)
DevicePort tap
(8 ports)
5m
(16 ft)
4m
(13 ft)
41853
Publication DNET-UM072C-EN-P - July 2004
1-10 Get Started
Wire
Color
white CAN_H signal signal
blue CAN_L signal signal
bare drain shield n/a
black V- power power
red V+ power power
Wire
Identity
Usage
Round
Usage
Flat
About direct connection
Connect devices directly to the trunk line only if you can later remove the devices
without disturbing communications on the cable system.This is called a
“zero-length” drop, because it adds nothing (zero) when calculating cumulative
drop line length.
IMPORTANT
If a device provides only fixed-terminal blocks for its
connection, you must connect it to the cable system by a
drop line. Doing this allows you to remove the device at the
tap without disturbing communications on the trunk line of
the cable system.
About connectors
Connectors attach cables to devices or other components of the DeviceNet
cable system. Field-installable connections are made with either sealed or open
connectors.
device with
removable
open-style
connector
device with
fixed, open-style
connector
41674
Connector Description
Sealed
Open Plug-in: Cable wires attach to a removable connector.
Mini-style: Attaches to taps and thick and thin cable.
Micro-style: Attaches to thin cable only - has a reduced
current rating.
Fixed: Cable wires attach directly to non-removable screw
terminals (or equivalent) on device.
41839
Publication DNET-UM072C-EN-P - July 2004
Get Started 1-11
Mini/Micro field-installable quick-disconnect (sealed) connectors (round
media only)
Screw terminals connect the cable to the connector. See Chapter 3 for
information about making cable connections.
blue
white
mechanical key
5
4
3
1
2
Micro Female
mechanical key
drain
red
2
1
3
4
black
5
white
blue
black
Additional configurations are available. Refer to the On-machine
Connectivity catalog, publication M115-CA001.
Catalog number
Description Thin Thick
Straight micro male 871A-TS5-DM1 n/a
Straight micro female 871A-TS5-D1 n/a
Right-angle micro male 871A-TR5-DM1 n/a
Right-angle micro female 871A-TR5-D1 n/a
Straight Mini male 871A-TS5-NM1 871A-TS5-NM3
Straight Mini female 871A-TS5-N1 871A-TS5-N3
Mini Female
drain
red
30489-M
Publication DNET-UM072C-EN-P - July 2004
1-12 Get Started
Plug-in field-installable (open) connectors
Most open-style devices ship with an open-style connector included. These
connectors are also shipped in packages of 10.
probe holes
Black
Blue
5-pin linear plug (open)
jack screwjack screw
Red
White
Shield or Bare
41707
mechanical key
Black
Blue
Black
Blue
5-pin linear to micro adapter
10-pin linear plug (open)
Red
White
Shield or Bare
Description Catalog number
mechanical key
jack screwjack screw
Red
White
Shield or Bare
41708
Publication DNET-UM072C-EN-P - July 2004
5-pin linear plug (open; with jack screws) 1799-DNETSCON
5-pin linear plug (open; without jack screws) 1799-DNETCON
10-pin linear plug (open) 1787-PLUG1OR
5-pin linear to micro male adapter 1799-DNC5MMS
2
Terminate
the Network
TR
Get Started 1-13
The terminating resistor reduces reflections of the communication signals on
the network. Choose your resistor based on the type of cable (round or flat) and
connector (open or sealed) you use.
TR
For round cable:
– the resistor may be sealed when the end node uses a sealed T-port tap
– the resistor may be open when the end node uses an open-style tap
For flat cable:
To verify the resistor connection, disconnect
power and measure the resistance across the
Can_H and Can_L lines (blue and white wires,
respectively). This reading should be
approximately 50-60Ω.
Do not put a terminating resistor on a node with
a non-removable connector. If you do so, you
risk network failure if you remove the node. You
must put the resistor at the end of the trunk line.
– the resistor is a snap-on cap for the KwikLink connector base, available
in sealed and unsealed versions
You must attach a terminating resistor of 121Ω, 1%, 1/4W or larger, to each end
of the trunk cable. You must connect these resistors directly across the blue and
white wires of the DeviceNet cable.
ATTENTION
If you do not use terminating resistors as described, the
DeviceNet cable system will not operate properly.
The following terminating resistors provide connection to taps and the trunk
line.
• sealed-style terminating resistors. Male or female connections attach to:
– trunk line ends
– T-Port taps
Female Side
Male Side
sealed male terminator
Description Catalog number
Sealed male terminator 1485A-T1M5
Sealed female terminator 1485A-T1N5
sealed female terminator
mini T-Port tap
Publication DNET-UM072C-EN-P - July 2004
41854
1-14 Get Started
Wire
Color
Wire
Identity
Usage
Round
white CAN_H signal signal
blue CAN_L signal signal
bare drain shield n/a
black V- power power
red V+ power power
Usage
Flat
• open-style terminating resistors. 121Ω, 1%, 1/4W or larger resistors
connecting the white and blue conductors in micro- or mini-style attach
to:
– open-style T-Port taps
– trunk lines using terminator blocks
121 Ω
Black
Blue
Shield or Bare
Catalog number 1485A-C2
Red
White
• KwikLink flat cable terminating resistors
The 121Ω resistor is contained in the snap-on interface module:
41827
• sealed terminator with an Insulation Displacement Connector (IDC)
base (NEMA 6P, 13; IP67) catalog number 1485A-T1E4
• unsealed terminator with IDC base (no gaskets) (NEMA 1; IP60)
catalog number 1485A-T1H4
Network end caps are included with each KwikLink terminator; see page 3-14
for complete installation instructions.
terminating resistor with end cap
30490-M
end cap
30479-M
Publication DNET-UM072C-EN-P - July 2004
power
3
Supply Power
Use the power supply to power the DeviceNet
cable system only. If a device requires a
separate 24V power source other than the
DeviceNet power source, you should use an
additional 24V power source.
supply
Get Started 1-15
Guidelines for supplying power
The cable system requires the power supply to have a rise time of less than 250
milliseconds to within 5% of its rated output voltage. You should verify the
following:
• the power supply has its own current limit protection
• fuse protection is provided for each segment of the cable system
– any section leading away from a power supply must have protection
• the power supply is sized correctly to provide each device with its
required power
• derate the supply for temperature using the manufacturer’s guidelines
DN
PS
T
u
n
r
k
drop
IMPORTANT
For thick cable and Class 2 flat cable, your national and
local codes may not permit the full use of the power system
capacity. For example, in the United States and Canada, the
power supplies that you use with Class 2 thick cable must
be Class 2 listed per the NEC and CECode. The total
node
node
power
current allowable in any section of thick cable must not
exceed 4A.
Class 1 power supplies allow for an 8A system, and the use
of Class 1 flat cable. See Appendix A for more information
about national and local codes. Appendix B, “Power
Output Devices”, provides important information to the
installer.
Choose a power supply
The total of all of the following factors must not exceed 3.25% of the nominal
24V needed for a DeviceNet cable system.
• initial power supply setting - 1.00%
• line regulation - 0.30%
• temperature drift - 0.60% (total)
• time drift - 1.05%
• load regulation - 0.30%
Publication DNET-UM072C-EN-P - July 2004
1-16 Get Started
Use a power supply that has current limit protection as described in national
codes such as NEC, Article 725.
To determine the required power supply
current:
1. Add the current requirements of all
devices drawing power from the
network.
For example:
6.3A
2. Add an additional 10% to this total
to allow for current surge.
e.g. 6.3A x 10% = 6.93A
3. Make sure the total of 2 is less
than the minimum name-plate
current of the power supply you are
using.
e.g. 6.3A < 8A and NEC/CECode
IMPORTANT
The dc output of all supplies must be isolated from the ac
side of the power supply and the power supply case.
If you use a single power supply, add the current requirements of all devices
drawing power from the network. This is the minimum name-plate current rating
that the power supply should have. We recommend that you use the
Allen-Bradley 24V dc power supply (catalog number 1787-DNPS) to comply
with the Open DeviceNet Vendor Association (ODVA) power supply
specifications and NEC/CECode Class 2 characteristics (if applicable).
About power ratings
Although the round thick cable and Class 1 flat cable are both rated to 8A, the
cable system can support a total load of more than 8A. For example, a 16A
power supply located somewhere in the middle of the cable system can supply
8A to both sides of the PowerTap™. It can handle very large loads as long as
no more than 8A is drawn through any single segment of the trunk line. However,
cable resistance may limit your application to less than 8A.
Drop lines, thick or thin, are rated to a maximum of 3A, depending on length.
The maximum current decreases as the drop line length increases.
Drop line length Allowable current
1.5m (5 ft) 3A
2m (6.6 ft) 2A
3m (10 ft) 1.5A
4.5m (15 ft) 1A
6m (20 ft) 0.75A
You may also determine the maximum current in amps (I) by using:
I = 15/L, where L is the drop line length in feet
I = 4.57/L, where L is the drop line length in meters
Publication DNET-UM072C-EN-P - July 2004
Get Started 1-17
The maximum allowable current applies to the sum of currents for all nodes on
the drop line. As shown in the example on page Page 1-7, the drop line length
refers to the maximum cable distance from any node to the trunk line, not the
cumulative drop line length.
• high maximum common mode voltage drop on the V- (black) and V+
(red) conductors
– the voltage difference between any two points on the V- conductor must
not exceed the maximum common mode voltage of 4.65V
• voltage range between V- and V+ at each node within 11 to 25V
Size a power supply
Follow the example below to help determine the minimum continuous current
rating of a power supply servicing a common section.
TR = terminating resistor
T = T-Port tap
PT = PowerTap tap
D = device
Results
power
supply 1
152m
(500 ft)
122m
(400 ft)
TRTRPT PTTT TTT
D1 D2 D3 D4 D5
1.50A 1.05A 0.25A 1.00A 0.10A
break V+ (red wire) here to separate
both halves of the network
power
supply 2
30m
(100 ft)
122m
(400 ft)
60m
(200 ft)
30m
(100 ft)
41831
Power supply 1
Add each device’s (D1, D2) DeviceNet current draw together for power supply
1 (1.50+1.05=2.55A)
2.55A is the minimum name-plate current rating that power supply 1 should
have. Remember to consider any temperature or environmental derating
recommended by the manufacturer.
IMPORTANT
This derating factor typically does not apply when you
consider the maximum short circuit current allowed by the
national and local codes.
Publication DNET-UM072C-EN-P - July 2004
1-18 Get Started
Results
Power supply 2
Add each device’s (D3, D4, D5) current together for power supply 2
(0.25+1.00+0.10=1.35A).
1.35A is the minimum name-plate current rating that power supply 2 should
have. Remember to consider any temperature or environmental derating
recommended by the manufacturer.
Place the power supply
DeviceNet networks with long trunk lines or with devices on them that draw
large currents at a long distance sometimes experience difficulty with common
mode voltage. If the voltage on the black V- conductor differs by more than 4.65
volts from one point on the network to another, communication problems can
occur. Moreover, if the voltage between the black V- conductor and the red V+
conductor ever falls below 15 volts, then common mode voltage could adversely
affect network communication. To work around these difficulties, add an
additional power supply or move an existing power supply closer to the heavier
current loads.
If possible, power supplies should be located at the middle of the network to
shorten the distance from the power supply to the end of the network.
To determine if you have adequate power for the devices in your cable system,
use the look-up method which we describe more fully in Chapter 4. See the
following example and figure (other examples follow in Chapter 4). You have
enough power if the total load does not exceed the value shown by the curve or
the table.
In a worst-case scenario, all of the nodes are assumed to be together at the
opposite end of the power supply, which draws all current over the longest
distance.
4171
IMPORTANT
This method may underestimate the total current capacity
of your network by as much as 4 to 1. See Chapter 4 to use
the full-calculation method if your supply does not fit
under the curve.
Publication DNET-UM072C-EN-P - July 2004
Current (amperes)
Get Started 1-19
A sample curve for a single, end-connected power supply is shown on the next
page.
Figure 1.1 One Power Supply (End Segment) KwikLink Cable (Flat)
NEC/CE Code Maximum
Current Limit
Network
Length
m (ft)
0 (0)
20 (66)
40 (131)
60 (197)
80 (262) 3.56
100 (328) 2.86
120 (394) 2.39
140 (459) 2.05
160 (525) 1.79
180 (591) 1.60
200 (656) 1.44
Length of trunk line, meters (feet)
Maximum
Current (A)
*
8.00
*
8.00
*
7.01
*
4.72
Network
Length
m (ft)
220 (722) 1.31
240 (787) 1.20
260 (853) 1.11
280 (919) 1.03
300 (984) 0.96
320 (1050) 0.90
340 (1115) 0.85
360 (1181) 0.80
380 (1247) 0.76
400 (1312) 0.72
420 (1378) 0.69
Maximum
Current (A)
41932
∗
Exceeds NEC CL2/CECode 4A limit.
IMPORTANT
This configuration assumes all nodes are at the opposite
end of the cable from the power supply.
Publication DNET-UM072C-EN-P - July 2004
1-20 Get Started
The following example uses the look-up method to determine the configuration
for one end-connected power supply. One end-connected power supply
provides as much as 8A near the power supply.
power
supply
106m
T
0.15A
(350 ft)
0.30A
0.10A
41833
53m
30m
23m
TR TR
TR = terminating resistor T = T-Port tap
PT = PowerTap tap D = device
(75 ft)
PT
(100 ft)
TTT
D1 D2 D3 D4
0.10A
(175 ft)
1. Determine the total length of the network.
Results
106m
2. Add each device’s current together to find the total current
consumption.
0.10 + 0.15+ 0.30 + 0.10 = 0.65A
IMPORTANT
Make sure that the required power is less than the rating of
the power supply. You may need to derate the supply if it is
in an enclosure.
3. Find the next largest network length using the table on page 1-19 to
determine the approximate maximum current allowed for the system.
120m (2.47A)
Since the total current does not exceed the maximum allowable current, the
system will operate properly (0.65A ≤ 2.47A).
IMPORTANT
If your application doesn’t fit “under the curve,” you may
either:
Publication DNET-UM072C-EN-P - July 2004
• Do the full-calculation method described in Chapter 4.
• Move the power supply to somewhere in the middle of
the cable system and reevaluate as described in the
previous section.
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